class_docstr: Generic data structure representing a directed graph with multiple edges.
code: def __init__(self) -> None:  # noqa :D
      # first key is the "from" node
      # second key is the "to" node
      self._adjacency_dict: Dict[KT, Dict[KT, List[VT]]] = {}
  
file_path: metricflow/metricflow/model/graph.py
imports: from __future__ import annotations
  from typing import Dict, Generic, List, Tuple, TypeVar
label_desc: Use image node_id 1 to create a new MultiDiGraph object from inherited base classes: Generic with example: obj = MultiDiGraph()